Showing posts with label Did you know ?. Show all posts
Showing posts with label Did you know ?. Show all posts

What causes Thunder?







Lightning does.In an instant, a bolt of lightning can heat the air around it up to  60,000 F . The heated air expands violently,  like an explosion. As the air expands it also cools quickly and starts to contract. This quick expansion and contraction air create the shock waves we hear as thunder.


Think of popping a balloon. When you blow it up, you are putting the air under pressure . Why? Because air molecules in the ballon are packed more tightly than they are in the air around it. The rubber keeps the air inside balloons from spreading out. When the balloon breaks, the air expands rapidly like the air superheated by lightning. The molecules from inside the balloon push against those on the outside creating shock wave that you hear as a pop". up. sound.

Why does chopping onions make your eyes water?




I am not the smell. The knife breaks open the onion's cells, letting out enzymes that react with other substances from the broken cells. A gas is formed mild sulfuric acid The front of the eye cornea has many sensitive nerve endings. They detect the irritation and alert the brain. The brain tells the tear ducts  (lachrymal glands ) to produce more water to clean the eyes.

What causes Rainbow?









The light we usually see the visible light is made up of different frequencies or colors in a certain range called the spectrum. The colors of the visible spectrum are red, orange, yellow, green, blue, indigo and violet. White light is a mixture of all these colors. A prism can separate the frequencies mixed in a beam of white light into the colors of the spectrum.

Some of Famous Scientists






1 . Tim Berners-Lee (1955) - , a Britsh computer which who radically changed the history of computing and communication when he invented the World Wide Web . in 1989.
Since then he has worked to make the Web grows as a source of  information about everything  under the sun. He works at the laboratory  in Massachusetts.

2. Nicolaus Copernicus (1473-1543), a Polish scientist known as the founder of modern astronomy. He came up with the theory that Earth and other planets revolve around the sun. At the time most people thought Earth was the center of the universe , and not much attention was paid to his theory.


Marie Curie  (1867-1934), a Polish-French physical chemist known for discovering radium, which  is used  to treat some diseases. She won the Novel Prize for chemistry in 1911.She and her husband , Pierre Curie, also won the Nobel Prize  for physics in 1903 for their work in radiation.









Charles Darwin (1809-1882), a British Scientist best known for his theory, living creatures slowly developed over millions of years into the forms they have today .




Thomas Edison (1847-1931) ,Ohio-born inventor who only attended school for three months. He created devices that transformed society, such as a reliable electric lightbulb , the electric generator, phonograph wireless telegraph m motion-picture projector, and alkaline, iron-nickel batteries.









Albert Einstein (1879-1955) , a German-American physicist who developed a revolutionary theory about the relationships between time , space, matter, and energy. He won Novel Prize in 1921.







Frederick Jones(1892-1961), changed our eating habits by inventing refrigerated trucks, eliminating the problem of food spoilage.




Johannes Kepler (1571-1630), German astronomer who developed three laws of planetary motion . He was the first to propose a force (later named gravity ) that governs planets orbits around the sun.



Ada lovelace (1815-1852), British mathematical genius who is considered the first computer programmer.She designed a language for the first computing machine invented by (Charles Babbage.)



Lise Meitner (1878-1968),  physicist who first discovered nuclear fission. She later predicted the chain reaction, which eventually led to the development of the atomic bomb, along with other nuclear energies,


Louis Eugene Neel (1904-2000) , a French physicist who discovered that  certain materials  that do not conduct electricity can still be magnetized. also led to the theory o plate tectonics.



Sir Isaac Newton (1642-1727) , a British scientist famous for many revolutionary discoveries. He worked out the basic of motion and gravity. He also showed that sunlight is made up of all the colors of the rainbow. He invented the branch of mathematics called calculus, but he this discovery quiet. Soon after a German philosopher and Mathematician named Gottfried Von Leibniz (1646-1716) also worked out a system of calculus, and made it widely known on his edge.


Wolfgan Pauli (1900-1958), Austrian American physicist who invented a famous rule of physics. I Says two electrons cannot occupy the same energy state in an atom at the same time. This helps explain why objects do not blend into each other. In 1931 he proposed the existence of a tiny particle, called a neutrino. Scientists confirmed 25 years later that it exists.

THE HUMAN DNA



What is DNA ?




Every cell n every living thing  or organism has DNA , A molecule that contains all the information about the organism . Lengths of connected DNA molecules, called genes, are like smallest pieces of a secret code. They determine  what each organism is like in great  detail.

Genes are passed on  from parents to children m and no two organism except identical twins have the same DNA. Many things about us - the color of our

eyes or hair, whether we're tall or short, the size of our feet depend on genes We inherited  from our parents.



DNA 'Fingerprints "



DNA is located in each of your cells , including your blood, saliva, hair follicles, and skin.  No one else has a DNA paternity exactly like yours .Using skin or hair collected at a crime scene and samples from a suspect, scientist  can analyze the makeup of the  same person. Cells from  persons at a crime scene can be evidence that the person was present at the crime DNA evidence is also used to show that some convicted people are innocent.





What makes us Human


The human genome is the DNA code for our species its's what makes us human beings .In 2000 the U.S. Human Genome Project reached a milestone .I identified the 3.1 Billion separate codes in human DNA. in 2001 , researchers reported that the human genome contains about  30,000 to  40,000 genes . For the first time ,We got an outline of the genetic code for the human  race.



Surprising , Humans don't have that many more genes than the roundworm , which has about  20,000 !  But we do have three times as many kinds of proteins called Alternative splicing. This means that the same genes can produce more than one kind of protein . By studying genes scientists can learn more about hereditary diseases and get a better idea of how human beings involved.


A history of Transportation Wind,Wheels , & Water






5000 B.C.
People harness animal-muscle power Oxen donkeys, ship & Camel to carry heavy loads.











3,500 B.C.
Egyptians create the first sailboat. Before this, people made rafts or canoes & paddled them with poles or their hands.





1,450's
Portugues build fast ships with three masts. These plus the compass usher in an age of exploration.

1730's






3,500 B.C. In Meso
potamian ( modern-day Iraq), people invented vehicles with wheels.But the first wheels are made of heavy wood, and the roads are terrible.


110 B.C.

Chinese invented the magnetic compass. It can allow them to sail long distances.


The 1660s


Horse-drawn stagecoaches begin to test running in France. They stop at stages to switch horses and passengers -the first mass transit system.



1769

James Watt patents the first succesful steam engine.






1807

Robert Fulton patents a highly efficient steamboat.

1830

Passenger rail service begins England with the Rocket, a steam train built by George Stephenson.It goes about 24 miles an hour or 1 day.



1839

At Kitty Hawk, Macmillan of Scotland invents the first pedaled bicycle.

1862

Etienne Lenoir of Belgium builds the first car with an internal-combustion engine.




1903


At Kitty Hawk, North Carolina, Orville Wright pilots the first powered heavier- than air machines a  12-13 second flight.



1908


Henry Ford builds the first Model T, a practical car for the general public.




1939

The first practical helicopter and first jet plane are invented. The jet flies up to 434 mph. Jet passenger service began in 1958.


1947

Flying 700 mph, U.s.  Air Force Capt. Charles Chuck Yeager breaks the siybd barrier in the jet-powered Bell X-1.


1961

Russian Cosmonaut Yuri  Gagarin orbits the Earth in a spaceship.







1969

U.s. astronauts aboard Apollo 11 land on the MOON.




1981

The Space Shuttle Columbia is the first reusable spacecraft with a human crew.




1997

British driver Andy Green breaks the sound barrier on land for the first time, going 763-764 mph.



2000
 Amtrak runs its northeast high-speed Acela train.It can go 150 miles an hour.